An alien space ship, in the shape of a bell, descends to Earth. Although the entire world's military has not been able to defeat the mother ship, aptly named Bell, it does not counter-attack, and thus after a while is not perceived as a threat. Black spheres, observation drones called Eyeballs, about the size of a small house, then appear in the world, and they adjust themselves to regular life, like waiting for a traffic light before crossing the street.

The students of the Magic User's Club do not believe these invaders are as innocent as they seem. And so, due to a joke gone wrong, club president Takakura Takeo together with his vice-president Aburatsubo Ayanojyo, and their three new members — the energetic klutz Sawanoguchi Sae, the level-headed tomboy Nakatomi Nanaka, and the gifted Aikawa Akane — decide to defeat the Bell using magic — even though half of the club members are not even able to fly yet!